Commutator



June 10 1924.

J. D. GREEN GOMMUTATOR Filed May 19. 1920 JACK D. GREEN z ven PatentedJune 10, 1924.

UNITED STATES JACK D. GREEN, OF LA. MANDA. PARK, CALIFORNIA.

COMMUTATOR.

Application filed May 19,

T @ZZ to tem it may concern.'

Be it known that l, JACK D. GREEN, a citiZen of the United States,residing at La Manda Park, in the county of Los Angeles and State ofCalifornia, have invented new and useful Improvements in Commutators, ofwhich the following is a specification.

This invention relates to a device for timing and controlling the sparkin the ignition system of internal combustion engines, and an object ofthe invention is to provide a means for opening and closing an electriccircuit at regular intervals and directing the current successively toeach of a series of conductors leading to sparking devices.

Another object is to provide a device of the above character embodying aseries of rolling contact members and a single wiper contact membermounted to be moved successively in and out of electrical engagementwith the roller contact members; and in which the parts are soconstructed and arranged as to be subjected to little wear and notliable to easily get out of order and which will permit ready removaland replacement of the parts.

A further object is to provide a commutator which is simple, durable,eflicient, and adapted to be produced at small cost.

Other objects will appear hereinafter.

The invention is illustrated in the accompanying drawings, in which:

Figure 1 is a view in elevation of the commutator as seen on its innerside.

Figure 2 is a view in vertical section as seen on the line 2 2 of Figure1.

Figure 3 is a detail in section as seen on the line 3 3 of Figure 1.

More specifically, l indicates the commutator casing or shell of anysuitable construction and adapted to be adjustably mounted on the wallof an engine (not shown) to extend over the end of a timing shaft 5 asis common in internal combustion engine construction; the shell lembodying an annular rim flange 6 arranged to encircle the shaft inspaced relation to and concentric therewith.

Extending through the flange and spaced at suitable intervals apart area series of conductor stems 7 which are threaded on their outer ends toform binding posts to which the terminals of electrical conductors maybe attached in the usual manner. Mounted on the inner ends of each stem7 is a turnable or rotary contact member 8 1920. Serial No. 382,465.

adapted to be engaged by a wiper contact member 9 mounted on a sleeve 10carried by the timing shaft 5.

The shell is formed with an end wall l1 from the margin of which theflange 6 projects providing a chamber in which the wiper contact memberis adapted to travel when the commutator is assembled and in operation;the wiper contact member being arranged to traverse a path of traveladjacent to the inner face f the end wall. A series of recesses 12 areformed on the inner face of the end wall in which the roller contactmembers 8 are disposed; the stems 7 eX- tending across the recesses andforming bearings for the rollers. A sleeve or bushing 14 is interposedbetween the stem and roller to provide a. wearing surface. For thepurpose of mounting the stems 7 they are preferably provided withthreaded inner end portions 15 which are screwed into the end walls ofthe recesses, as particularly shown in Figure 2, and nuts 16 are screwedon the outer end of the stems to bear againstthe shell and serve to lockthe stems against rotation. The terminals of electrical conductors (notshown) may be connected to the stems 7 in any desired manner, as anysort of fastening may be employed, such as is commonly used in devicesof this character.

The roller contact members 8 are of such diameter as to project a shortdistance beyond the inner face of the wall 11 to eX- tend in the path oftravel of the wiper contact member 9, and as a means for permitting thewiper contact member to readily ride in and out of engagement with theroller contact members it is formed with inclined flanges 17 on itsopposite edges which curve outwardly relative to the rollers.

The wiper contact member is here shown successively wipe the rollingcontact members and to passthereover in rolhng'contact therewith tocompleteelectrical connection between the shaft 5 and eachl of thestemsI sulating material, so as to'obviate the useof.l

separate insulators, thus permitting the commutator being formed of fewAparts which may be readily assembled and easily removed and replaced.

While I have shown and described a specific embodiment of myinvention, Ido not limit myself to the exact details' of con struction shown, butmay resort' to such changes and modifications as'occasion may requireand as may come within the scope of the appended claim,

I claim: v n

Inv a commutator, a shell having an end wall formed with a marginalflange, a series of fixedv stems4 extending thru the iiange radially ofthe shell each of said4 stems being fastened against turning andprojecting beyond the outer periphery' of the flange to form binding'posts, a bushing encircling each stem interiorly of the shell, a rollercontact member, mounted onl each of said bushings, a shaft over the endof which the shell isl mounted and a spring wiper contact member carriedon said sha-it adapted on rotation of the shaft to be moved successivelyinto contact with' the roller contact members and to ride over th'erollers in rolling contact therewith under tension.

JACK D. GREEN

